Subintimal re-entry device

ABSTRACT

A subintimal recanalization catheter, including an elongate shaft including a first tubular member and a penetration member slidably disposed in a lumen of the first tubular member. The penetration member includes a distal tip positioned proximal of a distal nose of the first tubular member. The distal nose of the first tubular member includes a ramp and a guide wire lumen extending through the distal nose of the first tubular member. Longitudinal movement of the penetration member relative to the first tubular member causes the penetration member to contact the ramp to direct the distal tip of the penetration member away from the first tubular member.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a continuation application of U.S. application Ser.No. 13/900,717, filed on May 23, 2013, which claims the benefit ofpriority under 35 U.S.C. §119(e) of U.S. Provisional Patent ApplicationSer. No. 61/651,273, filed on May 24, 2012, which are hereinincorporated by reference in their entirety.

TECHNICAL FIELD

This disclosure relates to devices and methods for recanalization of anoccluded blood vessel. More particularly, the disclosure is directed todevices and methods for re-entry into the true lumen from the subintimalspace of the blood vessel.

BACKGROUND

Chronic Total Occlusion (CTO) is an arterial vessel blockage thatobstructs blood flow through a vessel, and it can occur in both coronaryand peripheral arteries. In some instances, it may be difficult orimpossible to penetrate the CTO with a medical device in an antegradedirection to recanalize the vessel. Accordingly, techniques have beendeveloped for creating a subintimal pathway (a path between the intimaland adventitial tissue layers of the vessel wall) around the occlusionand then re-entering the true lumen of the vessel distal of theocclusion. In some instances, re-entering the true lumen from thesubintimal space and/or recanalization pathway may be difficult.Accordingly, it is desirable to provide alternative recanalizationdevices and/or methods having improved re-entry mechanisms forrecanalization of a blood vessel in which a CTO is present.

SUMMARY

The disclosure is directed to several alternative designs and methods ofusing medical device structures and assemblies, and uses thereof.

Accordingly, one illustrated embodiment is a catheter for recanalizing ablood vessel having an occlusion therein. The catheter includes anelongate shaft having a proximal end, a distal end, and a guide wirelumen extending therethrough to a distal guide wire port. The elongateshaft includes a proximal portion having a tubular shape and a distalportion having a flattened shape, the flattened shape including firstand second wings extending in opposite directions configured tofacilitate orientation of the distal portion within a subintimal spaceof a vessel. A deflection wire extends from the proximal end to thedistal end of the elongate shaft, wherein actuation of the deflectionwire causes the distal portion of the elongate shaft to deflect into acurved configuration to orient the distal guide wire port toward a truelumen of the vessel.

Another illustrative embodiment for re-entry into the true lumen fromthe subintimal space is a catheter including an elongate shaft includinga first tubular member and a penetration member slidably disposed in alumen of the first tubular member. The penetration member includes adistal tip positioned proximal of a distal nose of the first tubularmember. The distal nose of the first tubular member includes a ramp anda guide wire lumen extending through the distal nose of the firsttubular member. The longitudinal movement of the penetration memberrelative to the first tubular member causes the penetration member tocontact the ramp to direct the distal tip of the penetration member awayfrom the first tubular member.

Yet another illustrative embodiment is a method for recanalizing a bloodvessel having an occlusion therein. The method includes advancing aguide wire through a lumen of a blood vessel to a location proximal of aproximal end of an occlusion. A distal end of the guide wire is directedout of the lumen of the blood vessel and between a first tissue layerand a second tissue layer of a wall of the vessel to a location distalof a distal end of the occlusion. A recanalization catheter is advancedalong the guide wire with the guide wire passing through a guide wirelumen of the recanalization catheter. The recanalization catheterincludes a first tubular member and a penetration member slidablydisposed in a lumen of the first tubular member. The penetration memberincludes a distal tip positioned proximal of a distal nose of the firsttubular member, and the distal nose of the first tubular member includesa ramp and the guide wire lumen extending through the distal nose of thefirst tubular member. Furthermore, the distal nose is positioned betweenthe first tissue layer and the second tissue layer at a location distalof the distal end of the occlusion. The penetration member is actuatedrelative to the first tubular member to cause the penetration member tocontact the ramp and direct the distal tip of the penetration memberaway from the first tubular member, and re-enter the lumen of the bloodvessel distal of the distal end of the occlusion.

The above summary of some example embodiments is not intended todescribe each disclosed embodiment or every implementation of thepresent disclosure.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention may be more completely understood in consideration of thefollowing detailed description of various embodiments in connection withthe accompanying drawings, in which:

FIGS. 1A-1C illustrate an exemplary subintimal recanalization catheter,where FIG. 1A depicts the distal portion, and FIGS. 1B and 1C exhibittwo alternative embodiments of the proximal portion of the catheter;

FIG. 2 is an exemplary cross sectional view of the catheter apparatustaken across the plane 2-2;

FIGS. 3A-3B illustrate an alternative embodiment of the distal nose ofthe catheter;

FIGS. 4A-4B illustrate another embodiment of a subintimal recanalizationcatheter;

FIGS. 5A-5D illustrate cross-sectional views of the exemplary cathetershown in FIG. 4 taken along planes 5A-5A, 5B-5B, 5C-5C, and 5D-5Drespectively;

FIGS. 6A-6B exhibit another alternative embodiment of a subintimalrecanalization catheter;

FIG. 7 is an exemplary cross-sectional view of the catheter of FIG. 6Ataken along plane 7-7;

FIGS. 8A-8B illustrate two alternative routes for the guide wire withinthe embodiment of the catheter shown in FIG. 6A;

FIGS. 9A-9B illustrate an exemplary deflection mechanism to deflect thepenetration member towards the vessel lumen;

FIGS. 10A-10B depict another exemplary deflection mechanism to deflectthe penetration member towards the vessel lumen;

FIG. 11 is a side plan view of the embodiment of the catheter shown inFIGS. 6A-6B with the distal end of the penetration member projected awayfrom the elongate axis of the catheter;

FIGS. 12-16 illustrate aspects of an exemplary method for re-enteringthe true lumen of an occluded blood vessel using the catheter apparatusof FIGS. 1A-1B;

FIGS. 17A-17D illustrate aspects of another exemplary method forre-entering the true lumen of an occluded blood vessel using thecatheter apparatus of FIGS. 4A and 4B; and

FIG. 18 exhibits the penetration member of the catheter apparatus ofFIGS. 4A and 4B penetrating through the intima layer of the vessel wall.

While the invention of the present disclosure is amenable to variousmodifications and alternative forms, specifics thereof have been shownby way of example in the drawings and will be described in detail. Itshould be understood, however, that the intention is not to limitaspects of the invention to the particular embodiments described. On thecontrary, the intention is to cover all modifications, equivalents, andalternatives falling within the spirit and scope of the invention.

DETAILED DESCRIPTION

For the following defined terms, these definitions shall be applied,unless a different definition is provided in the claims or elsewhere inthis specification. All numeric values are herein assumed to be modifiedby the term “about,” whether or not explicitly indicated. The term“about” generally refers to a range of numbers that one of skill in theart would consider equivalent to the recited value (i.e., having thesame function or result). In many instances, the term “about” may beindicative as including numbers that are rounded to the nearestsignificant figure.

The recitation of numerical ranges by endpoints includes all numberswithin that range (e.g., 1 to 5 includes 1, 1.5, 2, 2.75, 3, 3.80, 4,and 5).

Although some suitable dimensions ranges and/or values pertaining tovarious components, features, and/or specifications are disclosed, oneof skill in the art, incited by the present disclosure, would understanddesired dimensions, ranges and/or values may deviate from thoseexpressly disclosed.

As used in this specification and the appended claims, the singularforms “a,” “an,” and “the” include plural referents unless the contentclearly dictates otherwise. As used in this specification and theappended claims, the term “or” is generally employed in its senseincluding “and/or” unless the content clearly dictates otherwise.

The following detailed description should be read with reference to thedrawings in which similar elements in different drawings are numberedthe same. The detailed description and the drawings, which are notnecessarily to scale, depict illustrative embodiments and are notintended to limit the scope of the invention. The illustrativeembodiments depicted are intended only as exemplary. Selected featuresof any illustrative embodiment may be incorporated into an additionalembodiment unless clearly stated to the contrary.

While the devices and methods described herein are discussed relative torecanalization of arterial vessels blocked by a CTO, it is contemplatedthat the devices and methods may be used in other applications, whererecanalization of a blood vessel is desired.

The present disclosure provides methods and systems to re-enter the truelumen of a blood vessel during recanalization of the blood vessel. Tothis end, the methods and systems may employ a catheter having acatheter shaft, a distal nose, and a penetration member, including aguide wire, and a guide wire lumen disposed within the catheter.

Exemplary Embodiments

An exemplary subintimal recanalization catheter 100 is illustrated inFIGS. 1A-1C. The catheter 100 includes a distal portion 100A shown inFIG. 1A, and a proximal portion 100B shown in FIG. 1B. Further, analternative embodiment of a proximal portion 100C is shown in FIG. 1C,respectively.

As illustrated in FIGS. 1A-1C, the catheter 100 may include a firsttubular member, an outer catheter shaft 102 extending between a proximalend 104 (shown in FIGS. 1B-C) and a distal end 106. In addition, in someinstances a second member, penetration member 108, may be slidablydisposed within the catheter shaft 102 between the proximal end 104 andthe distal end 106. In some embodiments, typically, a guide wire 112 mayact as the penetration member 108. In other instances, a separatepenetration member 108 may be used. A hub assembly 109 having one ormore ports may connect to the proximal end 104, and a distal nose 110may engage with the catheter shaft 102 at the distal end 106. The guidewire 112 may be slidably disposed within the penetration member 108 andthe distal nose 110. In some instances, the guide wire 112 may be thepenetration member 108. A distal tip 114 is disposed at the distal endof the distal nose 110, and the distal tip 114 may include a guide wireport 116 to extend the guide wire 112 or the penetration member 108distally beyond catheter 100.

The catheter 100 may be configured to be advanced over the guide wire112 for delivery to a remote location in the vasculature of a patient.In some embodiments, the catheter 100 may be configured as a SingleOperator Exchange (SOE) (Monorail or Rapid-Exchange) catheter having arapid exchange port 117 near the distal end 106 for inserting the guidewire 112 into a guide wire lumen 120. Alternatively, in some otherembodiments, the catheter 100 may be configured as an Over The Wire(OTW) catheter having a port 118 configured at hub assembly 109 forinserting the guide wire 112 into the guide wire lumen 120. It may benoted that in instances where the catheter 100 is an SOE, the proximalend 104 may not include the port 118. Where the catheter 100 is an OTW,however, the rapid exchange port 117 may be omitted.

As shown in FIGS. 1A-1C, the catheter shaft 102 may be an elongatesheath or a tubular member adapted to move forward into a blood vessellumen. The catheter shaft 102 may be configured with a substantiallycircular cross section extending between the proximal and distal ends104, 106. Other suitable cross-sectional shapes of the catheter shaft102 may be elliptical, oval, polygonal, or irregular. In addition, thecatheter shaft 102 may be flexible along its entire length or adaptedfor flexure along portions of its length. Flexibility may allow thecatheter shaft 102 to navigate through turns in body lumens, whilerigidity provides the necessary force to urge the catheter shaft 102forward. The cross-sectional dimensions of the catheter shaft 102 mayvary according to the desired application, but they are generallysmaller than the typical thickness of the blood vessel wall in locationswhere the catheter 100 may be used, such as in a coronary artery. Thelength of the catheter shaft 102 may vary according to the location ofthe vessel lumen where subintimal recanalization is to be conducted. Inaddition, the distal end 106 of the catheter shaft 102 may have atapering structure similar to a wedge or a cone. Alternatively, thedistal end 106 may not have a tapering structure. The hub assembly 109at the proximal end 104 may include components such as one or more portsto insert various medical devices into the lumen of the catheter shaft102. Furthermore, the hub assembly 109 may include a handle (not shown)for the operator to hold the catheter 100, and one or more actuationmeans (not shown) to control the guide wire 112 and/or the distal nose110.

Catheter shaft 102 may be made of any suitable biocompatible materialsuch as a polymeric or metallic material. The catheter shaft 102 mayalso be coated using a suitable low friction material, such as TEFLON®,polyetheretherketone (PEEK), polyimide, nylon, polyethylene, or otherlubricious polymer coatings, to reduce surface friction with thesurrounding tissues.

In instances in which the penetration member 108 is used in addition tothe guide wire 112, the penetration member 108 may be an elongate sheathslidably disposed within the guidewire lumen 120 of the catheter shaft102, where the guide wire 112 may be also slidably disposed coaxiallytherewith. In other instances, only one of the penetration member 108and the guide wire 112 may be present in the guidewire lumen 120 at thesame time, thus requiring removal of one of the guide wire 112 or thepenetration member 108 prior to advancing the other of the guide wire112 or the penetration member 108 through the guidewire lumen 120. Thepenetration member 108 may extend from the rapid exchange port 117 tothe distal end 106 in instances in which the catheter 100 is an SOEcatheter, or the penetration member 108 may extend from port 118 to thedistal end 106 in instances in which the catheter 100 is an OTWcatheter. The penetration member 108 may have a substantially circularcross-section. Alternatively, the cross-sectional shape of thepenetration member 108 may be any shape in which the guide wire 112 mayeasily maneuver, for instance, oval, polygonal, or tapering or any othershape capable of achieving the intended purpose in the intendedenvironment. The penetration member 108 may be flexible or adapted forflexure along portions of its length. The flexibility of the penetrationmember 108 may or may not depend upon the flexibility of the cathetershaft 102. The cross-sectional dimensions of the penetration member 108may be greater than the cross-sectional dimensions of the guide wire 112and less than the cross-sectional dimensions of the catheter shaft 102.The distal end of the penetration member 108 may or may not engage withthe distal nose 110 at the distal end 106. In some embodiments, such ascatheter 100 illustrated in FIGS. 1A-1C, the distal end of thepenetration member 108 may connect to the distal nose 110. Moreover, thelumen of the penetration member 108 may be co-axial with the lumen ofthe distal nose 110 such that the guide wire 112 may pass from thepenetration member 108 to the distal nose 110 without obstruction.

In some embodiments, the penetration member 108 may be formed of ametallic material, including a stainless steel or a nickel-titaniumalloy such as nitinol. Alternatively, a polymeric material such aspolyamide, polyether block amide, polyethylene, or polyethyleneterepthalate or a combination of polymeric and metallic materials may beused to form the penetration member 108.

Furthermore, a lubricious polymeric coating may be applied to the innerand/or the outer surface of the penetration member 108 to reducefriction between the penetration member 108 and the guide wire 112,and/or between the catheter shaft 102 and the penetration member 108.The lubricious polymeric coating may include suitable low frictionmaterials such as TEFLON®, polyetheretherketone (PEEK), polyimide,nylon, polyethylene, or any other lubricious polymer coatings.

As shown in FIG. 1A, the distal nose 110 may be a flattened structureengaged with and/or extending from the catheter shaft 102 at the distalend 106. The distal nose 110 may include the guide wire lumen 120extending through a flattened portion 122 (shown as wings 122A-122B).The flattened portion 122 may extend the surface area of the distal nose110 in a plane including the longitudinal axis of the distal nose 110,running along the length of the distal nose 110. In addition, theflattened portion 122 may facilitate in maintaining the orientation ofthe distal nose 110 parallel to the true lumen of a blood vessel duringuse as well as rotational orientation of the distal nose 110 such thatthe guide wire port 116 may be oriented toward the lumen of a bloodvessel when deflected.

The guide wire lumen 120 may be a hollow tubular structure that mayallow passage of the guide wire 112 and/or the penetration member 108therethrough and distally beyond the distal nose 110 into a blood vesselwhere the catheter 100 may be used. The guide wire lumen 120 may beconfigured with any suitable shape such as circular, oval, polygonal, orirregular. The guide wire lumen 120 may have cross-sectional dimensionsgreater than the cross-sectional dimensions of the guide wire 112 or thepenetration member 108. Further, the cross-sectional dimensions of theguide wire lumen 120 may be less than the thickness of the blood vesselwall where the subintimal recanalization catheter 100 may be used.

In the present embodiment, the flattened portion 122 includes two wings122A-122B attached to the guide wire lumen 120. The wings 122A-122B mayextend in opposite directions from the guide wire lumen 120. The wings122A-122B may be rectangular, circular, oval, regular, orirregular-shaped members attached to the guide wire lumen 120 in a planeincluding the longitudinal axis of the guide wire lumen 120. The wings122A-122B may be thicker near the guide wire lumen 120 and may taperregularly or irregularly towards the edges. Alternatively, the wings122A-122B may be thicker at the edges and may taper towards the guidewire lumen 120. The wings 122A-122B may have a curvature extendingoutwardly from the plane including the longitudinal axis of the guidewire lumen 120 in either the same or opposing directions. Furthermore,the wings 122A-122B or portions thereof may be flexible or adapted forflexure. The wings 122A-122B may flex in a vessel wall to adapt to theshape of the vessel wall and follow the curvature of the vessel wall.

FIG. 2 illustrates the cross section of the distal nose 110 taken acrossthe plane 2-2. As disclosed, in some embodiments, the wings 122A-122Bmay possess flexibility to adapt to the shape of a vessel wall. In somecircumstances, one or more reinforcing members may be included withinthe wings 122A-122B. The reinforcing members may facilitate the wings122A-122B in adapting to the shape of the vessel wall, and they mayfurther prevent the wings 122A-122B from flexing or bending intoundesired shapes. Some exemplary reinforcing members may be metallicribbons, braids, or wires. For example, as shown in FIG. 2, someembodiments may employ reinforcing strips 124 for shaping the distalnose 110. The strips 124 may run parallel to the elongate axis of thedistal nose 110, and each wing 122A or 122B may include only one of thestrips 124 or more than one of the strips 124. The strips 124 may be ofany suitable dimensions that may fit into the wings 122A-122B. Thestrips 124 may allow the wings 122A-122B to flex into certain shapes,such as, the shape of the vessel wall. In addition, the strips 124 mayprevent the wings 122A-122B from flexing into shapes that may hinder orobstruct the movement of the distal nose 110 within the vessel wall. Thestrips 124 may be made up of any polymeric or metallic materials such asstainless steel, nitinol, or polyamides to provide strength andstability to the wings 122A-122B. In some embodiments, as shown in FIG.2, the strips 124 may be metallic ribbons passing through a centralportion of each wing 122A-122B.

The wings 122A-122B may have dimensions suitable to separate and slidebetween the adventitia and intima layers of the desired blood vesselwhere the subintimal recanalization may be conducted. For example, thespan of the wings 122A-122B may be less than the circumference of thevessel wall. Moreover, the thickness of the wings 122A-122B may be lessthan the thickness of the vessel wall, in some instances.

FIGS. 3A-3B exhibit an alternative embodiment 300 of the distal nose(shown as distal nose 110 in FIG. 1A), where FIG. 3A illustrates a crosssectional view of the distal nose 300, and FIG. 3B exhibits aperspective view of the distal nose 300. In this embodiment, theflattened portion 122 is a paddle- or spatula-shaped member thatincludes the guide wire lumen 120. It may be noted that a person ofordinary skill in the art may envision many other embodiments for theflattened portion 122 capable of achieving the intended purpose in theintended environment. In general, the flattened portion 122 may be anymember attached to or formed with the catheter shaft 102 that mayincrease the surface area of the distal nose 300 (also show as distalnose 110 in FIG. 1A) in a plane including the longitudinal axis of thedistal nose 300.

The distal tip 114 of the distal nose 110 may be a blunt or atraumatictip shaped to prevent any inadvertent damage to a vessel walls uponcontact with the distal tip 114. The distal tip 114 may assume anyatraumatic shapes such as a blunt ball nose or a beveled or curved nosestructure capable of achieving the intended purpose in the intendedenvironment. Further, as discussed above in FIG. 1A, the distal tip 114may include the guide wire port 116 that may connect to the guide wirelumen 120 to extend the guide wire 112 distally beyond the distal tip114.

The distal nose 110 may be detachably connected, permanently coupled, orformed as an integral component of the catheter shaft 102. Distal nose110 may be coupled to distal end 106 by any suitable coupling mechanism,such as assemblies joined by welding, molding, a snap fit, screw fit,luer-lock, or other known attachment mechanisms capable of achieving theintended purpose in the intended environment. Suitable permanentcoupling methods may include adhesive bonding, molding, or welding,depending on the distal nose 110 and/or catheter shaft 102 material.Alternatively, distal nose 110 may be formed integral with the distalend 106 of the catheter shaft 102.

The distal nose 110 may be made up of any suitable biocompatiblematerial. For example, polymeric materials such as polyamide,polyetherblockamide, polyethylene, or polyethylene terepthalate may beused to make the distal nose 110. Alternatively, the distal nose 110, orportions thereof, may be made up of metallic materials such as stainlesssteel or nitinol, or a combination of polymeric and metallic materials.Further, in some embodiments, the guide wire lumen 120 and the wings122A-122B may be made up of different material, attached duringmanufacture. In other embodiments, the wings 122A-122B may be detachablefrom the guide wire lumen 120. Furthermore, in some embodiments, theguide wire lumen 120 and the wings 122A-122B may be formed as a singleintegral component.

A lubricious polymeric coating may be used at the inner and/or the outersurface of the distal nose 110 to reduce friction between the guide wirelumen 120 and the guide wire 112, and between the vessel walls and thewings 122A-122B. The lubricious polymeric coating may include suitablelow friction materials such as TEFLON®, polyetheretherketone (PEEK),polyimide, nylon, polyethylene, or any other lubricious polymercoatings.

As described, the guide wire 112 is a wire on which the catheter 100 maybe configured to move forward for delivery to a remote distal location.The guide wire 112 may be a metallic or polymeric wire and/or a stylet.In some embodiments, the guide wire 112 may be made up of biocompatiblematerials such as stainless steel or nitinol. The dimensions of guidewire 112 may depend on the application of the guide wire 112. Forexample, the length of the guide wire 112 may depend on the length ofthe catheter 100, the target location within the vasculature, and theextent to which the guide wire 112 may need to extend beyond the distaltip 114. In addition, the diameter of the guide wire 112 may be lessthan the cross sectional dimensions of the penetration member 108 and/orthe guide wire lumen 120 for insertion into the catheter 100.

The embodiments of the present disclosure may include a deflectionmechanism. The deflection mechanism may be any mechanism that maydeflect the distal nose 110 and/or the penetration member 108 towardsthe true lumen of a blood vessel when the distal nose 110 is present inthe subintimal space of the vessel wall. As shown in FIGS. 1B-C, thepresent embodiment of the disclosure illustrates the use of a pull wire126 as a deflection mechanism to deflect the distal nose 110 towards thetrue lumen of a blood vessel in a subintimal space. The pull wire 126may be disposed within the catheter shaft 102 extending from theproximal end 104 to the distal end 106 (shown in FIG. 1A) and throughthe distal nose 110 (shown in FIG. 1A). The pull wire 126 may bepositioned ventrally, below the guide wire lumen 120. The wings122A-122B of the flattened portion 122 may ensure proper rotationalorientation such that the pull wire 126 is positioned between the guidewire lumen 120 and the lumen of a blood vessel. In addition, the pullwire 126 may be connected to any mechanism that may exert actuationand/or tension proximally on the pull wire 126 to deflect the distalnose 110. For example, as shown in FIG. 1B, a rotatable knob 128attached to the pull wire 126 as a pull mechanism may be used.Alternatively, the embodiment 100C shown in FIG. 1C may include aslidable button 130 connected to the proximal end of the pull wire 126.It may be noted that the pull mechanisms 128, 130 illustrated in thedisclosure are merely exemplary, and a person skilled in the art mayutilize one of many suitable pull mechanisms known in the art to actuate(push or pull) the pull wire 126 capable of achieving the intendedpurpose in the intended environment.

Further, dimensions and construction of pull wire 126 may be tailored tospecific environments. For example, the pull wire 126 may have a lengthsuitable to extend from the distal tip 114 to the proximal end 104. Inaddition, the diameter of the pull wire 126 may be large enough toprovide the necessary strength to the pull wire 126 that may be requiredto deflect the distal nose 110.

Another embodiment of a re-entry catheter is illustrated in FIGS. 4A-4B,a catheter 400 including a distal portion 400A, shown in FIG. 4A, and aproximal portion 400B, shown in FIG. 4B. As shown in FIG. 4A, the distalportion 400A may include an opening 402 located proximally to the distalnose 110 near the distal end 106. In addition, the penetration member108 may not extent into or through the guide wire lumen 120 of thedistal nose 110, and the opening 402 may expose the distal end of thepenetration member 108. However, the distal tip 403 of the penetrationmember 108 may be positioned proximal to the distal nose 110 co-axiallyaligned to the guide wire lumen 120. Further, in an OTW design, theguide wire 112 may extend through the penetration member 108 to theguide wire lumen 120 via a port 405 located at the distal tip 403.

In some embodiments, the penetration member 108 may be considered as adeflectable re-entry or redirection tube and may deflect away from thecentral axis of the catheter shaft 102 to extend out of the opening 402.In that instance, the deflected penetration member 108 may aid the guidewire 112 to puncture and penetrate the intima layer of a blood vessel.In some instances, the penetration member 108 may include flexibilitycharacteristics permitting the penetration member 108 to be deflectableaway from the catheter shaft 102 into a curved or bent configuration. Inother instances, the penetration member 108 may include one or more cutsor slits 404 formed through the sidewalls of the penetration member 108,providing the penetration member 108 with a degree of lateralflexibility capable of achieving the intended purpose in the intendedenvironment. For example, the penetration member 108 may include ahelical cut or slit 404 formed through the sidewalls of the penetrationmember 108. The helical cut or slit 404 may extend partially around thecircumference of the penetration member 108 along a length of thepenetration member 108, or another arrangement of cuts or slits 404 maybe formed in another fashion to provide a desired degree of flexibilitycapable of achieving the intended purpose in the intended environment.In some embodiments, the penetration member 108 may be formed from ahypo-tube using a laser, water jet, or any other cutting mechanisms usedto form the cuts or slits 404 on the surface thereof. In some otherembodiments, the penetration member 108 may be manufactured with cutsand slits 404 using 3D printing technologies.

In some embodiments, the proximal portion 400B shown in FIG. 4B mayinclude an actuation device 406 that may facilitate an operator toactuate the penetration member 108 relative to the catheter shaft 102,to deflect the penetration member 108 towards the intima layer. Theactuation device 406 may be an electronic or mechanical switch, arotatable knob, push button, lever or other actuation mechanisms. Someexemplary deflection mechanisms are discussed in detail with FIGS. 9A-9Band 10A-10B below.

FIGS. 5A-5D illustrate cross-sectional views of the distal portion 400Ashown in FIG. 4A taken along the planes 5A-5A, 5B-5B, 5C-5C, and 5D-5Drespectively. In some embodiments, as shown in FIG. 5A, the cathetershaft 102 or a portion thereof may include an outer tubular member 502representing a cross section of the catheter shaft 102 across plane5A-5A. The penetration member 108 may extend through the lumen of theouter tubular member 502, and the guide wire 112 may extend through thelumen of the penetration member 108.

As discussed, FIG. 5B illustrates a cross section of the distal portion400A shown in FIG. 4A taken along plane 5B-5B. In some embodiments, asshown in FIG. 5B, the catheter shaft 102 (shown in FIG. 4A) or a portionthereof may include a crescent-shaped or “D” or “U”-shaped portion 508including a lumen 510. The penetration member 108 may extend exterior toand below the crescent-shaped or “D”-shaped portion 508 running parallelto the crescent-shaped or D-shaped portion 508. The guide wire 112 mayextend through the lumen of the penetration member 108. Referring toFIGS. 4A and 5B, the crescent-shaped or D-shaped portion 508 may definea cross section of the distal portion 400A across the plane 5B-5Bpassing through the opening 402. Similarly, in some embodiments thelumen 510 may provide a path to extend the guide wire 112 to the guidewire lumen 120 in the distal nose 110. As shown, the crescent-shaped orD-shaped portion 508 may not restrict the penetration member 108 frommoving towards the region opposite to the crescent-shaped or D-shapedportion 508.

As discussed, FIG. 5C illustrates a cross section of the distal portion400A as shown in FIG. 4A taken along plane 5C-5C. In some embodiments,as shown in FIG. 5C, the distal nose 110 (shown in FIG. 4A) or a portionthereof may include a winged tubular portion 516 with the guide wire 112passing through the lumen of the winged tubular portion 516. The wingedtubular portion 516 may include two wing-shaped structures 516A and 516Bextending in opposite directions from a tubular portion 516C.

Referring to FIGS. 4A and 5C, the winged tubular portion 516 may definea cross section of the distal nose 110 across the plane 5C-5C shown inFIG. 4A. Similarly, the tubular portion 516C may define a cross sectionof the guide wire lumen 120 and the two wing-shaped structures 516A-516Bmay describe wings 122A-122B of the distal nose 110.

As discussed, FIG. 5D illustrates a cross section of the embodiment ofFIG. 4A taken along the plane 5D-5D. FIG. 5D illustrates two exemplaryalternative embodiments 520A and 520B of a portion of the distal nose110 near the distal tip 114. As shown, the embodiment 520A may include atubular portion 522 and the guide wire 112 extending through the tubularportion 522. Referring to FIGS. 4A and 5D, the tubular portion 522 maydefine a cross section of the guide wire lumen 120 across the plane5D-5D shown in FIG. 4A. Similarly, the embodiment 520B may include acrescent-shaped or D-shaped portion 526 defining cross sections of theguide wire lumen 120 along with the guide wire 112 extending through thecrescent-shaped or D-shaped portion 526. The embodiment 520A exhibitsthat the guide wire lumen 120 may be a closed channel near the distaltip 114, while the embodiment 520B exhibits that the guide wire lumen120 may be an open channel.

FIGS. 6A-6B exhibit another alternative embodiment of the presentdisclosure. FIG. 6A exhibits a distal portion 600A and FIG. 6B depicts aproximal portion 600B of a catheter 600. As shown in FIG. 6A, thepenetration member 108 may include two or more ports 602 and 604 at alocation proximate to the proximal end of the opening 402. The ports 602and 604 are discussed further with FIG. 7. Furthermore, a distal portion606 of the penetration member 108 may extend from the port 604 towardsthe opening 402 such that the distal tip 403 of the distal portion 606may lie proximal of the proximal end of the distal nose 110 within theopening 402. In some embodiments, for example, embodiments similar tothe embodiment shown in FIGS. 1A-C, the distal portion 606 may engagewith the guide wire lumen 120 by allowing the guide wire 112 to extendto the guide wire lumen 120 through port 405. In some other embodiments,the distal portion 606 may flex away from the longitudinal axis of thecatheter shaft 102 through opening 402 directing the port 405 towards avessel lumen (not shown). Further, the proximal portion 600B of catheter600 shown in FIG. 6B may be similar to the proximal portion 400B ofcatheter 400 shown in FIG. 4B.

FIG. 7 is a cross-sectional view of the distal portion 600A shown inFIG. 6A taken along plane 7-7. As shown in FIG. 7, the catheter shaft102 or a portion thereof may include an outer tubular member 702defining the cross section of the catheter shaft 102 and the penetrationmember 108 extending through the outer tubular member 702. The ports 602and 604 may connect to the lumen of the penetration member 108. Theports 602 and 604 may allow the operator to extend the guide wire 112through alternative routes within the catheter 600. The alternativeroutes to extend the guide wire 112 are described below along with FIGS.8A-8B.

As described, FIGS. 8A-8B illustrate alternative routes for the guidewire 112 within the distal portion 600A of catheter 600 shown in FIG.6A. As shown in FIG. 8A, the operator may route the guide wire 112 fromthe penetration member 108 through port 602, lumen 510, and guide wirelumen 120 through the distal nose 110 to the guide wire port 116.Alternatively, as shown in FIG. 8B, the operator may route the guidewire 112 from within the penetration member 108 through port 604, distalportion 606, port 405 and guide wire lumen 120 through the distal nose110 to the guide wire port 116.

This feature of alternative routes may allow the operator to use thepenetration member 108 to deflect towards the true lumen of a bloodvessel within the vessel wall, which in turn may facilitate insubintimal re-entry through port 405. For example, if the guide wire 112is routed through the route shown in FIG. 8B, the distal portion 606 ofthe penetration member 108 may not deflect as the guide wire 112 mayobstruct deflection. However, if the guide wire 112 is routed throughthe route shown in FIG. 8A, the distal portion 606 may be free todeflect away from the central axis of the catheter shaft 102 and maydirect the port 405 towards the true lumen of a blood vessel within thevessel wall. After deflection, the guide wire 112 may be re-routedthrough the distal portion 606 and port 405 towards the vessel lumen.Many mechanisms, such as motors, hydraulics, strings, or shafts or othermechanisms capable of achieving the intended purpose in the intendedenvironment may be used to deflect the distal portion 606.

The following sections elaborate on some of the exemplary mechanisms todeflect the distal portion 606. It may be noted that in some embodimentssuch as the embodiment shown in FIG. 4A, the penetration member 108 maynot contain the ports 602 and 604. In such embodiments, the deflectionmechanisms may deflect the entire penetration member 108. Furthermore, aperson skilled in the art may appreciate that other embodiments may havea different deflection portion of the penetration member 108 and thedeflection process may deviate from the exemplary process described inthe following sections.

As discussed, FIGS. 9A-9B illustrate an exemplary deflection mechanismto deflect the penetration member 108 or its distal portion 606 towardsthe vessel lumen. FIG. 9A depicts a distal portion of a catheter 900with the penetration member 108 in a non-deflected position. FIG. 9Bdepicts the distal portion of the catheter 900 with the penetrationmember 108 in a deflected position. The catheter 900 may be similar tothe catheter 600 shown in FIGS. 6A-6B, and may include an additionalcomponent, a ramp 902 as a deflection mechanism.

As shown in FIG. 9A, the ramp 902 may be a portion of or affixed on thedistal nose 110 at the distal portion of the opening 402 having a slantrunning from its proximal end 904 near the central axis of the cathetershaft 102 to its distal end 906 at the edge of the catheter shaft 102.In addition, the ramp 902 may lie in a straight line with the centralaxis of the penetration member 108, in some instances.

Referring to FIG. 9B, in some embodiments, an actuation means such asthe actuation device 406 shown in FIGS. 4B and 6B may actuate thepenetration member 108 to move distally towards the ramp 902 toeffectuate the deflection process. Due to this distal motion, the distalportion 606 of the penetration member 108 may hit the ramp 902 near theproximal end 904 and may deviate towards the distal end 906 along theslant of the ramp 902. This deviation may in turn deflect the distalportion 606 away from the central axis of the catheter shaft 102.Alternatively, in some embodiments, the actuation device 406 may actuatethe distal nose 110 to move proximally along the central axis of thecatheter shaft 102.

FIGS. 10A-10B illustrate another exemplary deflection mechanism fordeflecting the penetration member 108 or its distal portion 606 towardsthe vessel lumen. FIG. 10A depicts a distal portion of the catheter 1000with the penetration member 108 in a non-deflected position. FIG. 10Bexhibits the distal portion with the penetration member 108 in adeflected position. The catheter 1000 may be similar to the catheter 600shown in FIGS. 6A-6B, and may include an actuable sleeve 1002 as adeflection mechanism.

In some embodiments, the penetration member 108 may be configured to becurved or deflected from a generally axially aligned configuration. Inan equilibrium configuration, the penetration member 108 may extend fromparallel to the catheter shaft 102 to a curved configuration in whichthe distal portion 606 of the penetration member 108 is curved away fromthe longitudinal axis of the catheter shaft 102. For example, the distalportion 606 may be manufactured with a curvature or a bent structuresuch that the distal portion 606 when not constrained by the sleeve 1002may automatically reconfigure to a curved position. In such embodiments,a mechanism to selectively hold and release the pre-curved distalportion 606 within the catheter shaft 102 may be required. FIGS. 10A-10Billustrate one such mechanism using the sleeve 1002 to constrain thedistal portion 606 in a straightened configuration.

As illustrated in FIG. 10A, the actuable sleeve 1002 may be a sheathcovering the catheter shaft 102 over the region of the opening 402. Thesleeve 1002 may act as constraint to prevent the distal portion 606 fromdeflecting away from the central axis of the catheter shaft 102. Thesleeve 1002 may be shaped such that it may extend over the cathetershaft 102. In addition, the sleeve 1002 may be made up of any metallicor polymeric material that may have enough strength to hold the curveddistal portion 606 within the catheter shaft 102.

Referring to FIG. 10B, in some embodiments an actuation means such asthe actuation device 406 shown in FIGS. 4B and 6B may actuate the sleeve1002. The actuation device 406 may be connected to the sleeve 1002 usingany element such as a wire, a string, or a shaft. In the illustratedembodiment of FIGS. 10A-10B, a wire 1004 may be connected to the sleeve1002 to actuate it. Upon actuation, the sleeve 1002 constraining thedistal portion 606 of the penetration member 108 may move proximallyalong the central axis of the catheter shaft 102 allowing the distalportion 606 to automatically curve (deflect) away from the central axisof the catheter shaft 102 and out through the opening 402 whenunconstrained by the sleeve 1002.

It may be noted that the exemplary mechanisms to deflect the distalportion 606 illustrated herein are merely exemplary and a person ofordinary skill in the art may contemplate many other mechanisms todeflect the sleeve 1002.

As discussed above in FIGS. 6A and 6B, the deflection of the distalportion 606 or the entire penetration member 108 may assist inre-entering the true lumen of a blood vessel through the inner vesselwall. FIG. 11 illustrates exemplary mechanisms for re-entry using thedeflected distal portion 606. In some embodiments, as shown in FIG. 11,the deflected distal portion 606 may route the guide wire 112 towardsthe true lumen of the vessel through port 405. The guide wire 112 maythen be advanced distally out of the distal port of the penetrationmember 108 and puncture the inner vessel wall to re-enter the true lumenof the vessel. Alternatively, the distal tip 403 of the penetrationmember 108 may be configured to facilitate piercing and/or dissection ofthe tissue layers of the blood vessel. For example, the tip 403 mayinclude a sharp, rigid, or piercing feature. In some embodiments, thetip 403 may include an angled distal edge, providing the tip 403 with asharpened cutting or piercing surface. The tip 403 may puncture thevessel wall and may route the guide wire 112 directly into the vessellumen. It may be noted that the re-entry mechanisms discussed above aremerely exemplary and a person of average skill in the art maycontemplate other mechanisms for re-entry into the true lumen of avessel using the deflected penetration member 108.

FIGS. 12-16 illustrate aspects of an exemplary method for re-enteringthe true lumen of an occluded blood vessel using the catheter 100 ofFIGS. 1A-1C. As shown in FIG. 12, a blood vessel 1200 typically hasthree tissue layers, an innermost layer or intima layer 1202 (tunicaintima), an intermediate layer or media layer 1204 (tunica media), andan outermost layer or adventitia layer 1206 (tunica adventitia), withthe media layer 1204 positioned between the intima layer 1202 and theadventitia layer 1206. The intima layer 1202 is a layer of endothelialcells lining the lumen 1208 of the vessel 1200, as well as asub-endothelial layer made up of mostly loose connective tissue. Themedia layer 1204 is a muscular layer formed primarily ofcircumferentially arranged smooth muscle cells. The adventitia layer1206, which forms the exterior layer of the vessel 1200, is made up ofloose connective tissue made up of fibroblasts and associated collagenfibers.

In some instances, a chronic total occlusion (CTO) 1210 may block theblood vessel 1200 and may stop the flow of fluids though the vessellumen 1208. In addition, it may be difficult or impossible to passthrough the occlusion 1210 in the lumen 1208 with a medical device torecanalize the vessel 1200. In such instances, it may be possible torecanalize the blood vessel 1200 through a subintimal approach using adevice such as, a subintimal recanalization catheter 100 (see FIG. 1).

As shown, the guide wire 112 may initially be moved forward through thelumen 1208 of the vessel 1200 to a location proximate a proximal end ofthe occlusion 1210, which is blocking the lumen 1208. The guide wire 112may then be moved forward to penetrate outward through the intima layer1202 at a location proximate a proximal end of the occlusion 1210 intothe wall of the vessel 1200. With the tip of the guide wire 112 locatedbetween the intima layer 1202 and the adventitia layer 1206, the guidewire 112 may be further moved distally in a subintimal manner to createa subintimal space between the intima layer 1202 and the adventitialayer 1206. The guide wire 112 may be moved forward in a subintimalmanner until the distal tip of the guide wire 112 is located distal ofthe distal end of the occlusion 1210 in the subintimal space created,such as by dissection of tissue layers of the wall of the vessel 1200.

As shown in FIG. 13, the recanalization catheter 100 may then be moveddistally over the guide wire 112. The catheter 100 may be moved forwardfrom the true lumen 1208, proximal of the occlusion 1210 into thesubintimal space between the intima layer 1202 and the adventitia layer1206, to a position in the subintimal space in which the distal nose 110or a portion of it is located distal of the distal end of the occlusion1210. The catheter 100 may then move forward into the subintimal spaceparallel to the intima layer 1202 until the catheter 100 or a portion ofit approaches the desired position (distal of the distal end of theocclusion 1210).

FIG. 14 exhibits a cross section of the distal position of the catheter100 positioned in the subintimal space created between the tissue layersof the vessel 1200 along the plane 14-14 distal of the occlusion 1210 inFIG. 13. As shown, the vessel 1200 includes three tissue layers 1202,1204, and 1206 along with the central lumen 1208 having the occlusion1210. In addition, the cross section of the catheter 100 within themiddle tissue layer 1204 includes a winged outer structure 122representing a cross section of the distal nose 110, showing the guidewire lumen 120 with the guide wire 112 disposed within the guide wirelumen 120. Furthermore, the pull wire 126 is oriented such that the pullwire 126 is located ventrally, below the guide wire lumen 120 within thewinged structure 122. Referring to FIGS. 13 and 14, the winged structure122 (distal nose 110) may aid in providing stability to the catheter 100(shown in FIG. 13) within the vessel 1200 by fixing the orientation ofthe catheter 100 parallel to the vessel lumen 1208 in the media layer1204. Moreover, the parallel orientation of the catheter 100 within thewall of the vessel 1200 may keep the pull wire 126 below the guide wirelumen 120 (radially inward), which in turn may ensure deflecting thedistal nose 110 towards the vessel lumen 1208 distal of the occlusion1210.

FIG. 15 illustrates the deflection of the distal tip 114 towards thevessel lumen 1208. When the distal nose 110 or a portion of itapproaches to a position distal of the occlusion 1210, the operator mayactuate the pull mechanism using the knob 128 or slidable button 130 orother actuation member to deflect the distal tip 114. Once the pull wire126 is pulled, it applies a deflecting force on the distal nose 110forcing it to curve radially inwards. As the pull wire 126 is disposedat a ventral location within the distal nose 110, the net force (actingon the distal nose 110) curves the distal nose 110 toward the vessellumen 1208, thereby deflecting the distal tip 114 towards the intimalayer 1202.

FIG. 16 depicts the guide wire 112 advancing distally from the distaltip 114 and penetrating the intima layer 1202 and re-entering the truelumen 1208 of the vessel 1200. As discussed, the pull wire 126 maydeflect the distal tip 114 towards the intima layer 1202, which guidesthe guide wire port 116 toward the intima layer 1202. The operator maythen extend the guide wire 112 distally through guide wire port 116toward the intima layer 1202. Further, the operator may force the guidewire 112 into the intima layer 1202 to puncture the intima layer 1202and enter the true lumen 1208 of the vessel 1200. This process mayrupture the intima layer 1202 and create a false lumen extending throughthe subintimal space from the proximal end to the distal end of theocclusion 1210.

FIGS. 17A-17D illustrate additional aspects of an exemplary method forre-entering the true lumen 1208 of an occluded blood vessel 1200 usingthe catheter 400 of FIGS. 4A and 4B or catheter 600 of FIGS. 6A and 6B.Similar to the method illustrated in FIGS. 12-16, as shown in FIG. 17A,the guide wire 112 may initially move forward through the lumen 1208 andpenetrate outward through the intima layer 1202 at a location proximatea proximal end of the occlusion 1210 into the vessel 1200. The guidewire 112 may then be advanced through the subintimal space to a locationdistal of the distal end of the occlusion 1210.

Further, as shown in FIG. 17B, the catheter 400 may then be advanceddistally over the guide wire 112 from the true lumen 1208, proximal ofthe occlusion 1210 into the subintimal space, to a position where thedistal nose 110 and the opening 402 is located distal of the distal endof the occlusion 1210.

As illustrated in FIG. 17C, once the opening 402 approaches the distalend of the occlusion 1210, the operator may use any suitable deflectionmechanism to deflect the penetration member 108 toward the lumen 1208.For example, the deflection mechanisms described in FIGS. 9A-9B and10A-10B may be used to deflect the penetration member 108 or its distalportion 606 to deflect and position the port 405 towards the intimalayer 1202 through the opening 402. For example, the operator mayadvance the penetration member 108 distally against the ramp 902 todeflect the penetration member 108.

FIG. 17D illustrates the guide wire 112 penetrating the intima layer1202. After deflection, the penetration member 108 may route the guidewire 112 through port 405 towards the intima layer 1202, as illustratedin FIG. 11. The operator may then extend the guide wire 112 from withinthe penetration member 108 towards the intima layer 1202 and may applyforce to it to puncture the intima layer 1202. The guide wire 112 maypuncture the intima layer 1202 and re-enter the true lumen 1208 of thevessel 1200.

Alternatively, as shown in FIG. 18, the deflection of the penetrationmember 108 with the sharp distal tip 403 may puncture the intima layer1202 to create a re-entry path for the guide wire 112 by positioning theport 405 within the true lumen 1208 of the vessel 1200.

Once a re-entry path is created across the occlusion 1210, eitherthrough the occlusion 1210 or around the occlusion 1210 via a subintimaltrack, one or more additional medical devices may be advanced throughthe blood vessel 1200 to enlarge the pathway and/or pass distally of theocclusion 1210 to perform a further medical procedure.

Those skilled in the art will recognize that aspects of the presentdisclosure may be manifested in a variety of forms other than thespecific embodiments described and contemplated herein. Accordingly,departure in form and detail may be made without departing from thescope and spirit of the present disclosure as described in the appendedclaims.

What is claimed is:
 1. A subintimal recanalization catheter, comprising:an elongate shaft including a first tubular member and a penetrationmember slidably disposed in a lumen of the first tubular member, whereinthe penetration member is configured to puncture an intima layer of ablood vessel; the first tubular member including a side-facing openingdisposed proximal of a distal nose and a guide wire lumen extendingthrough the distal nose of the first tubular member; the penetrationmember including a distal tip positioned within the opening proximal ofthe distal nose of the first tubular member; and an actuatable sleevesurrounding the opening and the distal tip of penetration member, theactuatable sleeve being actuatable between a first position in which thesleeve covers the distal tip of the penetration member and a secondposition in which the distal tip of the penetration member is exposedfrom the sleeve; wherein the distal tip of the penetration member ispermitted to deflect away from the first tubular member when the sleeveis in the second position.
 2. The subintimal recanalization catheter ofclaim 1, wherein the guide wire lumen extending through the distal noseextends from the side-facing opening to a distal tip of the distal nose.3. The subintimal recanalization catheter of claim 1, wherein thepenetration member includes a first guide wire exit port at the distaltip of the penetration member and a second guide wire exit port locatedproximal of the distal tip of the penetration member.
 4. The subintimalrecanalization catheter of claim 3, further comprising a guide wireextending through a lumen of the penetration member and through theguide wire lumen of the distal nose of the first tubular member.
 5. Thesubintimal recanalization catheter of claim 4, wherein the guide wire ispermitted to selectively extend from one of the first guide wire exitport and the second guide wire exit port.
 6. The subintimalrecanalization catheter of claim 5, wherein the distal tip of thepenetration member is prevented from deflecting away from the firsttubular member when the actuatable sleeve is in the first position andthe guide wire extends through the guide wire lumen of the distal nose.7. The subintimal recanalization catheter of claim 6, wherein the guidewire extends through the first guide wire exit port and the guide wirelumen of the distal nose.
 8. The subintimal recanalization catheter ofclaim 7, wherein the distal tip of the penetration member is permittedto deflect away from the first tubular member when the actuatable sleeveis in the second position and the guide wire has been withdrawn from theguide wire lumen of the distal nose.
 9. The subintimal recanalizationcatheter of claim 5, wherein the distal tip of the penetration member ispermitted to deflect away from the first tubular member when theactuatable sleeve is in the second position and the guide wire extendsthrough the guide wire lumen of the distal nose.
 10. The subintimalrecanalization catheter of claim 9, wherein the guide wire extendsthrough the second guide wire exit port and the guide wire lumen of thedistal nose.
 11. The subintimal recanalization catheter of claim 3,wherein the first guide wire exit port of the penetration member isco-axial with the guide wire lumen through the distal nose of the firsttubular member.
 12. The subintimal recanalization catheter of claim 1,wherein when the distal tip of the penetration member is unconstrainedby the sleeve, the distal tip of the penetration member is permitted tobe deflected into a curved configuration.
 13. The subintimalrecanalization catheter of claim 12, wherein the distal tip of thepenetration member is biased to assume the curved configuration whenunconstrained.
 14. The subintimal recanalization catheter of claim 13,wherein the distal tip of the penetration member is pre-configured toassume the curved configuration when unconstrained.
 15. A method ofrecanalizing a blood vessel having an occlusion therein, the methodcomprising: i) advancing a guide wire through a lumen of a blood vesselto a location proximal of a proximal end of an occlusion; ii) directinga distal end of the guide wire out of the lumen of the blood vessel andbetween a first tissue layer and a second tissue layer of a wall of thevessel to a location distal of a distal end of the occlusion; iii)advancing a recanalization catheter along the guide wire with the guidewire passing through a guide wire lumen of the recanalization catheter,the recanalization catheter including a first tubular member and apenetration member slidably disposed in a lumen of the first tubularmember, the penetration member including a distal tip positionedproximal of a distal nose of the first tubular member, the distal noseof the first tubular member including a guide wire lumen extendingthrough the distal nose of the first tubular member; iv) positioning thedistal nose of the first tubular member of the recanalization catheterbetween the first tissue layer and the second tissue layer at a locationdistal of the distal end of the occlusion; v) retracting a sleevecovering the distal tip of the penetration member to expose the distaltip of the penetration member, wherein longitudinal movement of thesleeve relative to the first tubular member permits the distal tip ofthe penetration member to deflect away from the first tubular member;and vi) re-entering the lumen of the blood vessel distal of the distalend of the occlusion with the distal tip of the penetration member. 16.The method of claim 15, wherein the guide wire extends through a lumenof the penetration member while the recanalization catheter is advancedalong the guide wire.
 17. The method of claim 16, further comprising:prior to step v), retracting the guide wire proximally of the distal tipof the penetration member.
 18. The method of claim 16, wherein the lumenof the penetration member is co-axial with the guide wire lumen throughthe distal nose of the first tubular member.
 19. The method of claim 16,wherein the penetration member includes a first guide wire exit port atthe distal tip of the penetration member and a second guide wire exitport located proximal of the distal tip of the penetration member; andwherein the method further includes the steps of: vii) withdrawing adistal end of the guide wire into the lumen of the penetration memberthrough the second guide wire exit port; and viii) then advancing thedistal end of the guide wire out of the penetration member through thefirst guide wire exit port.